On Wed, Apr 22, 2015 at 08:54:34AM +0200, Martin Pieuchot wrote: > On 17/04/15(Fri) 16:47, Dimitris Papastamos wrote: > > Hi, > > > > This patch adds an option to usbdevs(8) to disable USB bus probing > > at runtime. The operation is restricted to the root user. > > It would be nice to show if probing is on or off, for example > > # usbdevs -p > bus probing: on > > # usbdevs -p off > > But other people might have better suggestions.
Yeah I thought about that, I will add it. > > I am not sure if this approach is sensible or even correct. Some > > pointers would be much appreciated. > > Setting a variable per hub (and here roothub) is overkill, a global > would be enough. Will fix. > How did you try it? What happen if you plug a hub with multiple > devices, turn bus probing off then detach the hub? I have not tried connecting a hub, but connecting a device with probing on, disabling probing and then removing works as expected by first detaching the device and disallowing any further probes after disabling them. I will try with a hub too. > What happen if you plug a device like a phone that use the power to > charge its battery after turning probing off. If I read your diff > correctly you still allow the device to be charged which is fine. Did > you try that? I think it's worth a documentation note. Not tried this yet, but will do. On a side note, What do you think of using a sysctl instead of an ioctl? I guess an ioctl will do but it would make it easy for people to disable this at boot time by simply adding the relevant knob in /etc/sysctl.conf. Otherwise I imagine people adding usbdevs -p off in rc.local. Cheers, Dimitris
